Brown spider

Brown spider

The brown spider, belonging to the genus Loxosceles, is a group of spiders known for their necrotic venom. These spiders are often referred to as recluse spiders or fiddleback spiders, due to the distinctive violin-shaped marking on their dorsum. The genus Loxosceles contains numerous species, with the Loxosceles reclusa, or the brown recluse spider, being one of the most notorious in North America.

Description

Brown spiders are typically small to medium in size, with body lengths ranging from 6 to 20 millimeters. They have a uniform brown color, which can vary from a light tan to a deep, dark brown. The hallmark violin-shaped mark is not present in all species within the genus, but when it is, it serves as a key identification feature. These spiders have six eyes, arranged in pairs, which is unusual as most spiders have eight eyes.

Habitat

Brown spiders are predominantly found in warmer climates. In the United States, the brown recluse spider is commonly found in the Midwest and South. They prefer dry, secluded areas such as woodpiles, closets, garages, and other undisturbed places. Internationally, species of Loxosceles can be found in various parts of the world, including South America, Africa, and Europe.

Behavior

Brown spiders are nocturnal and tend to avoid human contact. They are not aggressive and typically bite only when pressed against the skin or disturbed. The spiders use a necrotic venom that can cause significant medical issues in humans. However, not all bites result in severe symptoms, and the severity can vary based on the amount of venom injected and the individual's response to it.

Medical Significance

The bite of a brown spider can lead to loxoscelism, a condition characterized by necrosis of the skin and underlying tissues. Initial symptoms may include mild pain and redness, progressing to a severe necrotic lesion with a sunken appearance. Systemic symptoms, such as fever, chills, and malaise, can also occur but are less common. Treatment focuses on wound care and pain management, with severe cases sometimes requiring surgical intervention.

Prevention

Preventive measures against brown spider bites include reducing clutter in and around the home, using caution when moving stored items, and wearing gloves in areas where spiders may reside. Regular pest control can also help manage spider populations.

See Also

• Spider bite
• Venomous spiders
• Arachnology